A pilot study on pyroptosis related genes in peripheral blood mononuclear cells of non-small cell lung cancer patients.

OBJECTIVE: To investigate the GSDMD, CASP1, CASP4 and CASP5 expression in peripheral blood mononuclear cells of non-small cell lung cancer patients and analyze their clinical significance. METHODS: 71 non-small cell lung cancer patients were selected as the study group and 50 healthy individuals as the control group. The GSDMD, CASP1, CASP4 and CASP5 expression in peripheral blood mononuclear cells of the two groups were detected by real-time fluorescence quantitative PCR. The GSDMD, CASP1, CASP4, CASP5 expression and their relationship with the clinical characteristics of the patients were analyzed. RESULTS: Compared with the control group, the GSDMD, CASP4 and CASP5 expression in PBMCs of lung cancer patients was significantly higher(P < 0.05). Lymph node metastasis had significant difference with the CASP4 and GSDMD expression (P < 0.05); tumor volume had significant difference with CASP1 and CASP5 expression (P < 0.05). The areas under predictive ROC curve of the GSDMD, CASP1, CASP4, and CASP5 mRNA expression were 0.629(P < 0.05), 0.574(p > 0.05), 0.701(P < 0.05) and 0.628(P < 0.05), the sensitivity values were 84.5%, 67.6% 43.7%, and 84.3%;the specificity values were 42%, 52%, 84% and 64%, respectively. CONCLUSION: GSDMD, CASP1, CASP4 and CASP5 gene expression are highly increased in PBMCs of non-small cell lung cancer patients and their expression are closely related to the clinical characteristics of patients. The early enhanced pyroptosis-related gene expression may be potential molecular markers for early diagnosis of non-small cell lung cancer.

Validation of reference genes for the normalization of the RT-qPCR in peripheral blood mononuclear cells of septic patients.

Objective: To screen and validate reference genes suitable for gene mRNA expression study in peripheral blood mononuclear cells (PBMCs) between septic patients and healthy controls (HC). Methods: Total RNA in PBMCs was extracted and RT-qPCR was used to determine the mRNA expression profiles of 9 candidate genes, including ACTB, B2M, GAPDH, GUSB, HPRT1, PGK1, RPL13A, SDHA and YWHAZ. The genes expression stabilities were assessed by both geNorm and NormFinder software. Results: YWHAZ was the most stable gene among the 9 candidate genes evaluated by both geNorm and NormFinder in mixed and sepsis groups. The most stable gene combination in mixed group analyzed by geNorm was the combination of GAPDH, PKG1 and YWHAZ, while that in sepsis group was the combination of ACTB, PKG1 and YWHAZ. Conclusion: Our first systematic analysis of the reference genes in PBMC of septic patients suggested YWHAZ was the best candidate. The combination of ACTB, PKG1 and YWHAZ could improve RT-qPCR accuracy in septic patients. Our results identified the most stable reference genes to standardize RT-qPCR of sepsis patients, which can serve as a useful tool for gene function exploration in the future.

Increased Dp71 in ischemia-reperfusion injured rat heart exerts anti-apoptotic role via enhancing Bcl-2.

For the first time, increased Dp71 in ischemia-reperfusion injured rat heart were identified, both Dp71 mRNA and protein reached its peak expression 8 h after reperfusion. In H2O2 stimulated H9c2 cells, Dp71 mRNA and protein gradually increased and reached a peak at 16 h. Enhanced Dp71 in H9c2 could resist H2O2-induced cell apoptosis, while Dp71 depletion accelerated the apoptosis induced by H2O2. Enhanced Bcl-2 expression and Bcl-2∕Bax protein expression ratio was identified in Dp71 overexpressed H9c2 cells, while knocking down Dp71 significantly decreased the Bcl-2 and Bcl-2∕Bax protein expression ratio. Increased Dp71 can accelerate FAK and p65 phosphorylation, which finally resulted in enhanced Bcl-2 expression and explains the highly possible cardiac protection role of Dp71.

Cigarette smoke extract mediates cell premature senescence in chronic obstructive pulmonary disease patients by up-regulating USP7 to activate p300-p53/p21 pathway.

OBJECTIVES: Tobacco hazard is one of the most severe public health issues in the world. It is believed that smoking is the most important factor leading to chronic obstructive pulmonary disease (COPD). Endothelial progenitor cells (EPCs) originate from the bone marrow and can effectively repair vascular endothelial damage and improve vascular endothelial function. Current studies suggest that EPCs senescence and EPCs depletion exist in smoking-related COPD, but the molecular mechanism remains unclear. METHODS: Co-immunoprecipitation was used to detect the interaction between USP7 and p300. EPCs from smoking COPD patients were isolated, and the expressions of USP7 and p300 were detected by RT-PCR and Western Blot. Different concentrations of cigarette smoke extract (CSE) and USP7 or p300 inhibitors were used to treat EPCs, then the expression of p53, p53 target genes and aging-related genes were detected. Cell Counting Kit - 8 (CCK8) was used to detect cell proliferation, flow cytometry was used to detect cell cycle distribution, ß-galactosidase (ß-gal) staining and Lamp1 immunofluorescence was used to detect the proportion of aging cells. COPD mouse models were used to confirm the molecular mechanism. RESULTS: USP7 and p300 interacted with each other, and USP7 affected the protein stability of p300 by regulating the ubiquitination of p300. There existed high expressions of USP7 and p300 proteins in EPCs of smoking COPD patients and COPD mouse model. CSE promoted the high expressions of USP7 and p300 in EPCs. Further studies showed that CSE mediated the USP7/p300-dependent high expression of p53 and activated the expression of p53 target genes especially p21. Activation of p53 - p21 pathway finally inhibited cell activity, led to cell cycle arrest and premature senescence of EPCs. CONCLUSION: CSE mediated up-regulation of USP7 and p300 activated p53 - p21 pathway was a molecular mechanism that might lead to COPD.

lncRNA IGF2-AS Regulates Nucleotide Metabolism by Mediating HMGA1 to Promote Pyroptosis of Endothelial Progenitor Cells in Sepsis Patients.

BACKGROUND: Sepsis is one of the major causes of death worldwide, and its high mortality and pathological complexity hinder early accurate diagnosis. We aimed to investigate lncRNA IGF2-AS and HMGA1 effects on pyroptosis of endothelial progenitor cells (EPCs) in sepsis patients and the mechanisms involved. METHODS: Blood samples from sepsis patients and healthy subjects were collected, and EPCs were isolated and identified. We constructed cell lines that knocked down lncRNA IGF2-AS, HMGA1, and TYMS. Furthermore, lncRNA IGF2-AS was overexpressed. Subsequently, dNTP treatment with different concentrations was performed to investigate lncRNA IGF2-AS and HMGA1 effects on pyroptosis of EPCs in sepsis patients. Finally, exosomes were isolated from bone marrow mesenchymal stem cells (MSCs) to detect lncRNA IGF2-AS expression, and the influence of MSC-derived exosomal lncRNA IGF2-AS on sepsis was preliminarily discussed. RESULTS: Compared with Healthy group, lncRNA IGF2-AS, HMGA1, and TYMS were highly expressed in Sepsis group. Compared with si-NC group, si-lncRNA IGF2-AS group had increased proliferation ability, decreased pyroptosis, decreased HMGA1, RRM2, TK1, and TYMS expressions. lncRNA IGF2-AS played a regulatory role by binding HMGA1. Compared with si-NC group, the proliferation ability of si-HMGA1 group increased, pyroptosis decreased, and RRM2, TK1, and TYMS expressions also decreased. Compared with si-NC group, pyroptosis in si-TYMS group was reduced. In addition, HMGA1 was related and bound to TYMS. After overexpressing lncRNA IGF2-AS, dNTP level decreased, while the proliferation increased and pyroptosis decreased with higher concentration of dNTP. In addition, we found that EPCs took up MSC-exosomes. Compared with supernatant group, lncRNA IGF2-AS was expressed in exosomes group. Compared with EPCs group, EPCs+exosomes group had increased lncRNA IGF2-AS expression and increased pyroptosis. CONCLUSIONS: lncRNA IGF2-AS regulated nucleotide metabolism by mediating HMGA1 to promote pyroptosis of EPCs in sepsis patients. This study provided important clues for finding new therapeutic targets for sepsis.

Sirtuin 6 regulates macrophage polarization to alleviate sepsis-induced acute respiratory distress syndrome via dual mechanisms dependent on and independent of autophagy.

BACKGROUND AIMS: Sepsis-induced acute respiratory distress syndrome (ARDS) can be mediated by an imbalance in macrophage polarization; however, the underlying mechanisms remain poorly understood. This study aimed to investigate the modulatory role of sirtuin 6 (SIRT6) in macrophage polarization during sepsis-induced ARDS. METHODS: A mouse ARDS model was established using cecal ligation and puncture. Isolated alveolar macrophages (AMs) and lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDMs) were adopted as in vitro models. Macrophage polarization was evaluated by measuring M1 and M2 macrophage percentages via flow cytometry and expression of specific markers. The expression of microtubule-associated light chain protein 3I/II and beclin-1 was detected for assessing macrophage autophagy. Binding between specificity protein 1 (SP1) and the target gene promoter was evaluated using a chromatin immunoprecipitation assay. RNA expression was analyzed by quantitative reverse transcription polymerase chain reaction and western blotting. RESULTS: Treatment with the SIRT6 activator UBCS039 significantly alleviated lung injury in the mouse ARDS model and enhanced autophagy and M2 polarization in isolated AMs. M2 polarization and autophagy in LPS-challenged BMDMs were also effectively promoted by UBCS039 treatment or SIRT6 overexpression. An adenosine monophosphate-activated protein kinase inhibitor (Compound C) or autophagy inhibitor (3-methyladenine) partially abrogated M2 polarization mediated by SIRT6 overexpression upon LPS exposure. SIRT6 induced autophagy and M2 polarization of BMDMs partially via its deacetylase activity. SIRT6 inhibited mammalian target of rapamycin transcription by modulating SP1 to promote BMDM M2 polarization, which was independent of autophagy. CONCLUSIONS: SIRT6 promotes M2 polarization of macrophages to alleviate sepsis-induced ARDS in an autophagy-dependent and -independent manner.

Ginsenoside Rg3 alleviates septic liver injury by regulating the lncRNA TUG1/miR-200c-3p/SIRT1 axis.

BACKGROUND: Studies have shown that ginsenoside R3 (Rg3) plays a protective role in sepsis-induced organ injuries and mitochondrial dysfunction. Long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) is regarded as a regulator in sepsis. However, the association between TUG1 and Rg3 remains elusive. METHODS: A sepsis mouse model was established by caecal ligation and puncture (CLP), and liver injury was induced by haematoxylin-eosin (H&E) staining. Lipopolysaccharide (LPS) was used to induce hepatocyte damage. The expression levels of TUG1, microRNA (miR)-200a-3p, and silencing information regulator 1 (SIRT1) were examined by quantitative real-time polymerase chain reaction (qRT-PCR) assays. Cell viability was monitored using the Cell Counting Kit-8 (CCK-8) assay. MitoSOX Red staining and CBIC2 (JC-1) dye were employed to detect mitochondrial reactive oxygen species (ROS) and mitochondrial transmembrane potential (MTP) levels, respectively. The interaction between miR-200a-3p and TUG1 or SIRT1 was confirmed via dual-luciferase reporter or RNA immunoprecipitation (RIP) assay. RESULTS: Rg3 upregulated TUG1 expression in liver tissues of CLP mice and LPS-induced hepatocytes. Rg3 could activate autophagy to improve mitochondrial dysfunction in LPS-treated hepatocytes, which was partially reversed by TUG1 depletion or miR-200a-3p overexpression. Importantly, TUG1 targeted miR-200a-3p to activate the SIRT1/AMP-activated protein kinase (AMPK) pathway in LPS-treated hepatocytes. Moreover, gain of TUG1 ameliorated mitochondrial dysfunction in LPS-treated hepatocytes by sequestering miR-200a-3p. CONCLUSION: Our study revealed that Rg3 increased TUG1 expression and reduced miR-200a-3p expression to stimulate the SIRT1/AMPK pathway, thereby enhancing autophagy to improve sepsis-induced liver injury and mitochondrial dysfunction.

ROCK1 regulates sepsis-induced acute kidney injury via TLR2-mediated endoplasmic reticulum stress/pyroptosis axis.

BACKGROUND: It has been reported that ROCK1 participates in the progression of multiple diseases, including septic intestinal barrier, cardiac dysfunction and acute lung injury. However, its regulatory role and specific mechanism in sepsis-induced acute kidney injury (AKI) remain unclear. METHODS: Cecal ligation puncture (CLP) was conducted to establish sepsis mouse model, and in vitro model was achieved by lipopolysaccharide (LPS) stimulation. Genes expression was evaluated by qRT-PCR, western blot or ELISA was conducted to assess the levels of proteins. Hoechst staining was performed to evaluate cell pyroptosis. LDH activity assay was detected to assess cytotoxicity. Immunohistochemistry was conducted to detect Ly-6G expression and neutrophils distribution in kidney tissues of mice. H&E and TUNEL staining were carried to evaluate kidney injury of mice. RESULTS: Our findings illuminated that ROCK1 was highly expressed in sepsis-induced AKI, and ROCK1 knockdown inhibited NLRP3-mediated cell pyroptosis in LPS-induced HK-2 cells. Moreover, ROCK1 modulated HK-2 cell pyroptosis by regulating endoplasmic reticulum stress (ERS). TLR2 inhibitor could suppress ERS mediated cell pyroptosis under LPS treatment. Further, TLR2 activator partially reversed the effects of ROCK1 inhibition on ERS mediated pyroptosis in LPS-treated HK-2 cells and CLP mice. CONCLUSION: In conclusion, ROCK1 may regulate sepsis-induced AKI via TLR2-mediated ERS/pyroptosis axis. Our data demonstrated the role and underlying mechanism of ROCK1 in septic AKI, providing theoretical basis for sepsis-induced AKI treatment.

lncRNA PVT1 modulates NLRP3­mediated pyroptosis in septic acute kidney injury by targeting miR­20a­5p.

Acute kidney injury (AKI) is the most common complication of sepsis. The current incidence of sepsis is high (0.3% of total population) worldwide, and septic AKI may cause death in patients. Long non­coding (lnc)RNAs serve important roles in the pathogenesis of AKI. Therefore, the present study investigated the mechanism underlying lncRNA plasmacytoma variant translocation 1 (PVT1)­mediated regulation of pyroptosis in septic AKI. Septic kidney injury was induced in mice using the caecal ligation and puncture method, and lipopolysaccharide (LPS)­induced HK­2 cell models were also established. Haematoxylin­eosin staining was performed to assess pathological alterations of kidney tissues in the mice. The levels of IL­1ß, IL­18 and lactate dehydrogenase were determined by conducting ELISAs. Reverse transcription­quantitative PCR was used to detect the expression levels of PVT1 and microRNA (miR)­20a­5p. To assess pyroptosis, the protein expression levels of nucleotide­binding oligomerization domain­like receptor protein 3 (NLRP3), IL­1ß, IL­18, apoptosis­associated speck­like protein containing a CARD and cleaved caspase­1 were measured via western blotting. Flow cytometry was performed to assess the rate of cell pyroptosis. Dual luciferase reporter assays were used to assess the binding relationships of PVT1/miR­20a­5p and miR­20a­5p/NLRP3. PVT1 expression was significantly increased, whereas miR­20a­5p expression was significantly decreased in sepsis model mice and LPS­induced HK­2 cells compared with sham mice and control HK­2 cells, respectively. PVT1 knockdown significantly suppressed cell pyroptosis and downregulated the expression of inflammatory factors in LPS­induced HK­2 cells. The results also indicated that PVT1 served as a sponge of miR­20a­5p, and miR­20a­5p directly targeted NLRP3. miR­20a­5p knockdown significantly promoted LPS­induced cell pyroptosis. Moreover, PVT1 knockdown inhibited LPS­induced cell pyroptosis by targeting the miR­20a­5p/NLRP3 signalling pathway. The results of the present study suggested that PVT1 modulated NLRP3­mediated pyroptosis in septic AKI by targeting miR­20a­5p, which might suggest significant potential therapeutic targets for septic AKI.

Ginsenoside Rg1 Regulates SIRT1 to Ameliorate Sepsis-Induced Lung Inflammation and Injury via Inhibiting Endoplasmic Reticulum Stress and Inflammation.

OBJECTIVES: To investigate the protective effect of ginsenoside Rg1 on relieving sepsis-induced lung inflammation and injury in vivo and in vitro. METHODS: Cultured human pulmonary epithelial cell line A549 was challenged with LPS to induce cell injury, and CLP mouse model was generated to mimic clinical condition of systemic sepsis. Rg1 was applied to cells or animals at indicated dosage. Apoptosis of cultured cells was quantified by flow cytometry, along with ELISA for inflammatory cytokines in supernatant. For septic mice, lung tissue pathology was examined, plus ELISA assay for serum cytokines. Western blotting was used to examine the activation of inflammatory pathways and ER stress marker proteins in both cells and mouse lung tissues. Reactive oxygen species (ROS) level was quantified by DCFDA kit. RESULTS: Ginsenoside Rg1 treatment remarkably suppressed apoptosis rate of LPS-induced A549 cells, relieved mouse lung tissue damage, and elevated survival rate. Rg1 treatment also rescued cells from LPS-induced intracellular ROS. In both A549 cells and mouse lung tissues, further study showed that Rg1 perfusion significantly suppressed the secretion of inflammatory cytokines including tumor necrosis factor- (TNF-) alpha and interleukin- (IL-) 6 and relieved cells from ER stress as supported by decreased expression of marker proteins via upregulating sirtuin 1 (SIRT1). CONCLUSION: Our results showed that ginsenoside Rg1 treatment effectively relieved sepsis-induced lung injury in vitro and in vivo, mainly via upregulating SIRT1 to relieve ER stress and inflammation. These findings provide new insights for unrevealing potential candidate for severe sepsis accompanied with lung injury.

Ginsenoside Rg3 attenuates sepsis-induced injury and mitochondrial dysfunction in liver via AMPK-mediated autophagy flux.

Sepsis-led mitochondrial dysfunction has become a critical pathophysiological procedure in sepsis. Since ginsenosides have been applied in the treatment of mitochondrial dysfunction, ginsenoside Rg3 was employed to study its effects on the mitochondrial dysfunction induced by sepsis. The apoptosis rate, oxygen consumption rate (OCR), reactive oxygen species (ROS), antioxidant glutathione (GSH) pools, and mitochondrial transmembrane potential (MTP) were determined in LPS-induced sepsis hepatocytes treated with different concentrations of Rg3. Then, the protein expression levels of mitochondrial biogenesis related transcription factors, autophagy-related proteins, and AMP-activated protein kinase (AMPK) signal pathway related proteins were determined by Western blotting in both in vitro and in vivo sepsis models. Rg3 shows functions of promotion of OCR, attenuation of ROS, and maintenance of GSH pools, and its conjugating activity in the in vitro sepsis models. Rg3-treated cells were observed to have a higher MTP value compared with the LPS only induced cells. Moreover, Rg3 treatment can inhibit mitochondrial dysfunction via increasing the protein expression levels of mitochondrial biogenesis related transcription factors. Rg3 treatment has the function of inhibitor of apoptosis of human primary hepatocytes, and Rg3 can up-regulate the autophagy-related proteins and activate AMPK signal pathway in sepsis models. Meanwhile, the mitochondrial protective function exerted by Rg3 decreased after the autophagy inhibitors or AMPK inhibitor treatment in LPS-induced human primary hepatocytes. Rg3 can improve mitochondrial dysfunction by regulating autophagy in mitochondria via activating the AMPK signal pathway, thus protecting cell and organ injuries caused by sepsis.

Comparison of bone marrow tissue- and adipose tissue-derived mesenchymal stem cells in the treatment of sepsis in a murine model of lipopolysaccharide-induced sepsis.

Mesenchymal stem cells (MSCs) have been reported to regulate the systemic inflammatory response and sepsis-induced immunologic injury pre-clinically. However, whether MSCs from different sources elicit identical effects remains to be elucidated. The present study compared the effect of bone marrow­derived MSCs (BMSCs) and adipose tissue-derived MSCs (ADMSCs) in a murine model of lipopolysaccharide (LPS)­induced sepsis. SPF BALB/c mice were induced with an injection of LPS (10 mg/kg; 1 mg/ml) via the tail vein. To compare the effect of MSCs on the septic mice, either saline, BMSCs or ADMSCs were injected via the tail vein 5 min following the administration of LPS. The survival rates and body temperatures of the mice were observed regularly up to 48 h. The serum levels of pro­inflammatory cytokines, including tumour necrosis factor­α, interleukin (IL)­6 and IL­8, anti­inflammatory cytokines, including IL­2, IL­4 and IL­10, and biochemical markers, including lactate, creatinine, alanine aminotransferase and aspertate aminotransferase, were analyzed at 6 h. The BMSCs and ADMSCs significantly reduced mortality rates, body­temperature fluctuations, serum levels of biochemical markers and the majority of cytokines. However, the levels of IL­8 in the BMSC and ADMSC groups were increased and decreased, respectively. These findings suggested that BMSCs and ADMSCs ameliorated sepsis-associated organ injury and mortality, and had a similar regulatory effect on pro­ and anti­inflammatory cytokines despite the different MSC sources. Therefore, BMSCs and ADMSCs may serve as novel treatment modalities for sepsis.